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[Objective] The Three Gorges Reservoir’s impoundment has speed up habitat fragmentation and patching in the water level fluctuation zone, and extreme habitat stress has seriously damaged the structure and function of vegetation. Clarifying the habitat status of the water level fluctuation zone of the Three Gorges Reservoir, proposing an adaptive vegetation restoration strategy, and reconstructing the comprehensive ecological function of damaged river corridor are of utmost importance for building regional ecological security pattern and ensuring water resources security of the Yangtze River Basin. [Methods] In response to the prominent issues of vegetation degradation and ecological function damage, we systematically analyzed multiple habitat conditions and their influence on riparian vegetation growth. Focusing on the basic requirements for ecological restoration of damaged river corridor along reservoir banks, a vegetation restoration pattern for construction of suitable microhabitats and optimization of vegetation functional pattern was explored. [Results] The habitat conditions of the water level fluctuation zone were jointly regulated by unique water level rhythm formed by reservoir, operation, climate condition during the exposed, soil erosion and sedimentation and soil environment, which presented a distinctive spatial heterogeneity pattern. Among these, inundation duration, emergence time, and inundation intensity by seasonal water fluctuation were the primary factors affecting plant reproduction and development, while soil erosion, sedimentation burial and soil substrates affected vegetation growth. [Conclusion] Accordingly, water level, site conditions and morphological-functional trait characteristics of various vegetation should be comprehensively considered when planning vegetation restoration in the water level fluctuation zone. Meanwhile, the high-quality stress-resistant species selection, site preparation measures for soil condition improvement, and the zonal optimization of vegetation patterns were beneficial for rebuilding the comprehensive ecological function of the water level fluctuation zone. This provided theoretical support and scientific basis for the ecological management of the water level fluctuation zone in the Three Gorges Reservoir.

Naked-eye 3D micro-LED display combines the characteristics of 3D display with the advantages of micro-LED. However, the 3D micro-LED display is still at the conceptual stage, limited by its intrinsic emission properties of large divergence angle and non-coherence, as well as difficulties in achieving large viewing angles with high luminous efficiency. In this work, we propose a double-layer metasurface film integrating functions of collimation with multiple deflections, constituting a micro-LED naked-eye 3D display system. The system is characterized through numerical simulations using the 3D finite-difference time-domain method. The simulation results show that the double-layer metasurface film restricts 90% of the emitted light of the micro-LED to the vicinity of the 0° angle, improving its spatial coherence. Subsequently, a large-angle, low-crosstalk outgoing from −45° to 45° is achieved, while providing a deflection efficiency of over 80% and a pixel density of up to 605. We believe this design provides a feasible approach for realizing naked-eye 3D micro-LED displays with a large field of view, low crosstalk, and high resolution.

Chemotherapy for advanced non-small-cell lung cancer (NSCLC) remains the first treatment choice. Angiogenesis inhibitors are effective for lung cancer treatment. This study explored whether chemotherapy combined with angiogenesis inhibitors could achieve better efficacy in NSCLC. The zebrafish A549 xenograft model was used to investigate the combined effect of apatinib and chemotherapeutic agents in NSCLC. Apatinib combined with pemetrexed demonstrated the highest antitumor effect compared with apatinib combined with gemcitabine or paclitaxel in vitro. In the zebrafish A549 xenograft model, apatinib and pemetrexed, alone or in combination, showed significant inhibition of tumor growth. Co-treatment with apatinib and pemetrexed demonstrated the best antitumor effects, suggesting that the combination of apatinib and pemetrexed might be a promising alternative therapy for patients with lung cancer. Apatinib combined with pemetrexed had enhanced antitumor effects compared with either one alone in the zebrafish model of NSCLC.

Optical microcavities are known for their strongly enhanced light–matter interactions. Whispering gallery mode (WGM) microresonators have important applications in nonlinear optics, single-mode output, and biosensing. However, there are few studies on resonance modes in the ultraviolet spectrum because most materials with high absorption properties are in the ultraviolet band. In this study, the performance of a microdisk cavity based on boron nitride (BN) was simulated by using the Finite-difference time-domain (FDTD) method. The WGM characteristics of a single BN microdisk with different sizes were obtained, wherein the resonance modes could be regulated from 270 nm to 350 nm; additionally, a single-mode at 301.5 nm is achieved by cascading multiple BN microdisk cavities. Moreover, we found that a BN microdisk with a diameter of 2 μm has a position-independent precise sensitivity for the nanoparticle of 140 nm. This study provides new ideas for optical microcavities to achieve single-mode management and novel coronavirus size screening, such as SARS-CoV-2, in the ultraviolet region.

This work has presented gas sensors based on indium tin oxide (ITO) for the detection of SO2 and NO2. The ITO gas-sensing material was deposited by radio frequency (RF) magnetron sputtering. The properties of gas sensing could be improved by increasing the ratio of SnO2. The response characteristics of the gas sensor for detecting different concentrations of NO2 and SO2 were investigated. In the detection of NO2, the sensitivity was significantly improved by increasing the SnO2 ratio in ITO by 5%, and the response and recovery time were reduced significantly. However, the sensitivity of the sensor decreased with increasing SO2 concentration. From X-ray photoelectron spectroscopy (XPS) analysis, the gas-sensitive response mechanisms were different in the atmosphere of NO2 and SO2. The NO2 was adsorbed by ITO via physisorption but the SO2 had a chemical reaction with the ITO surface. The gas selectivity, temperature dependence, and environmental humidity of ITO-based gas sensors were systematically analyzed. The high detection sensitivity for acidic gas of the prepared sensor presented great potential for acid rain monitoring.

Abstract Background Intrahepatic cholestasis of pregnancy (ICP) is a common gestational complication characterized by pruritus and elevated bile acids, usually occurring in the third trimester when the serum estrogen and progesterone levels are highest. Hyperandrogenism during pregnancy is a pathological state that is mostly induced by polycystic ovary syndrome (PCOS) but rarely by concomitant androgen-secreting ovarian tumours. To date, no correlation has been drawn between ICP and hyperandrogenism. Case presentation Here, we present a rare case of early-onset severe ICP in a PCOS patient conceived via in vitro fertilization-embryo transfer, with worsening hirsutism and acne due to high levels of testosterone and dehydroepiandrosterone sulphate, both of which were produced by a fast-growing ovarian Sertoli–Leydig cell tumour. Her serum estradiol was also very high, which was speculated to be converted from the circulating androgens by the placenta. She had preterm premature rupture of membranes and delivered at 30 weeks, followed by a rapid remission of ICP as her serum estradiol dropped. However, the excessive androgens did not retreat until the large ovarian tumour was surgically removed. Conclusion This unusual case highlights the concurrence of original hyperandrogenism and subsequent hyperestrogenism during pregnancy and the resultant confounding manifestations. Obstetricians should be aware of the potential association between androgen excess and ICP via placental aromatization.

Abstract Intrauterine adhesion (IUA) is a common gynaecological disease that develops from infection or trauma. IUA disease may seriously affect the physical and mental health of women of childbearing age, which may lead to symptoms such as hypomenorrhea or infertility. Presently, hysteroscopic transcervical resection of adhesion (TCRA) is the principal therapy for IUAs, although its function in preventing the recurrence of adhesion and preserving fertility is limited. Pharmaceuticals such as hormones and vasoactive agents and the placement of nondegradable stents are the most common postoperative adjuvant therapy methods. However, the repair of injured endometrium is relatively restricted due to the different anatomical structures of the endometrium. Recently, the treatment outcome of IUAs has improved with the advancement of hysteroscopic techniques. In particular, the application of bioactive scaffolds combined with tissue engineering technology has proven to have high therapeutic potential or endometrial repair in IUA treatment. Herein, this review has summarized past therapeutic strategies, including postoperative adjuvant therapy, cell or therapeutic molecular delivery therapy methods and bioactive scaffold-based tissue engineering methods. Therefore, this review presented the recent therapeutic strategies for repairing endometrium treatment and pointed out the issues of clinical concern to provide alternative methods for the management of IUAs.

ABSTRACT Due to the changes in pathogenic species and the absence of research on topical skin antibiotics, the therapy of skin and soft tissue infections (SSTIs) is facing more and more severe challenges. It is particularly urgent to look for alternative therapies without induction of drug resistance. UV C (UVC) light within the range of 200 to 280 nm is one of the most common techniques used to kill and/or inactivate pathogenic microorganisms. However, the traditional most commonly used wavelength of 254 nm irradiated from a low-pressure mercury lamp is hazardous to human health, being both carcinogenic and damaging to eye tissues, which limits its applications in vivo. This research aimed to investigate the antimicrobial properties and influence of 275-nm UVC light from a light-emitting diode (UVC-LED light) on wound healing time. Five bacteria, three fungi, and scalded-mouse models combined with SSTIs were used to evaluate the antimicrobial effect in vitro and in vivo. 275-nm UVC-LED light inactivated both bacteria and fungi with a very short irradiation time in vitro and induced neither DNA damage nor epidermal lesions in the mice’s skin. Furthermore, in mouse models of SSTIs induced by either methicillin-resistant Staphylococcus aureus (MRSA) or Candida albicans, the 275-nm UVC-LED light showed significant antimicrobial effects and shortened the wound healing time compared with that in the no-irradiation group. UVC-LED light at 275 nm has the potential to be a new form of physical therapy for SSTIs. IMPORTANCE As a common clinical problem, the therapy of SSTIs is facing growing challenges due to an increase in the number of drug-resistant bacteria and fungi. UV C (UVC) light sterilization has been widely used in all aspects of daily life, but there are very few reports about in vivo therapy using UVC light. It is well known that prolonged exposure to UVC light increases the possibility of skin cancer. In addition, it is also very harmful for eyes. UV irradiation with 254-nm UVC light can cause corneal damage, like thinning of the corneal epithelial layer, superficial punctate keratitis, corneal erosion, etc. In this study, we focused on looking for a more accessible light source and safer UVC wavelength, and 275-nm UVC LED light was chosen. We investigated its applicability for SSTIs therapy with relative skin safety and expected that it could be used as a new physical therapy method for SSTIs.

Spatially resolved photoluminescence at the sub-micro scale was used to study the optical non-uniformity of the micro-LED under varied power density excitation levels. The trend of the efficiency along injection levels were found to be highly dependent on the location of the chip mesa. The sidewall was 80% lower than the center under low-power density excitation, but was 50% higher under high-power density excitation. The external quantum efficiency droop at the center and the sidewall was 86% and 52%, respectively. A 2 µm band area near the sidewall was characterized where the efficiency and its trends changed rapidly. Beyond such band, the full width at half maximum and peak wavelength variation across the chip varied less than 1 nm, indicating high uniformity of the material composition. The sudden change = in the band, especially under high level excitation indicates the indium composition change formed by ion residues on the sidewall affect the distribution of charge carriers. These findings contribute to the understanding of cause of efficiency disadvantage and non-uniformity problems in small-size micro-LEDs.

The application of deep ultraviolet detection (DUV) in military and civil fields has increasingly attracted the attention of researchers’ attention. Compared with the disadvantages of organic materials, such as complex molecular structure and poor stability, inorganic materials are widely used in the field of DUV detection because of their good stability, controllable growth, and other characteristics. Rapid advances in preparing high-quality ultrawide-bandgap (UWBG) semiconductors have enabled the realization of various high-performance DUV photodetectors with different geometries, which provide an avenue for circumventing numerous disadvantages in traditional detectors. Herein, the development history and types of DUV detectors are briefly introduced. Typical UWBG detection materials and their preparation methods, as well as their research and application status in the field of DUV detection, are emphatically summarized and reviewed, including III-nitride semiconductors, gallium oxide, diamond, etc. Finally, problems pertaining to DUV detection materials, such as the growth of materials, the performance of devices, and their future development, are also discussed.

The emergent optical activity (OA) caused by anisotropic light emitter in microcavities is an important physical mechanism discovered recently, which leads to Rashba–Dresselhaus photonic spin-orbit (SO) coupling. In this study, we report a sharp contrast of the roles of the emergent OA in free and confined cavity photons, by observing the optical chirality in a planar–planar microcavity and its elimination in a concave–planar microcavity, evidenced by polarization-resolved white-light spectroscopy, which agrees well with the theoretical predictions based on the degenerate perturbation theory. Moreover, we theoretically predict that a slight phase gradient in real space can partially restore the effect of the emergent OA in confined cavity photons. The results are significant additions to the field of cavity spinoptronics and provide a novel method for manipulating photonic SO coupling in confined optical systems.

Serological tests are important diagnostic and disease surveillance tools for addressing the COVID-19 pandemic. Here, the authors present a tri-part Nanoluciferase based assay to detect antibodies against SARS-CoV-2.

Epilepsy is a common and severe chronic neurological disorder. Recently, post-translational modification (PTM) mechanisms, especially protein acetylation modifications, have been widely studied in various epilepsy models or patients. Acetylation is regulated by two classes of enzymes, histone acetyltransferases (HATs) and histone deacetylases (HDACs). HATs catalyze the transfer of the acetyl group to a lysine residue, while HDACs catalyze acetyl group removal. The expression of many genes related to epilepsy is regulated by histone acetylation and deacetylation. Moreover, the acetylation modification of some non-histone substrates is also associated with epilepsy. Various molecules have been developed as HDAC inhibitors (HDACi), which have become potential antiepileptic drugs for epilepsy treatment. In this review, we summarize the changes in acetylation modification in epileptogenesis and the applications of HDACi in the treatment of epilepsy as well as the mechanisms involved. As most of the published research has focused on the differential expression of proteins that are known to be acetylated and the knowledge of whole acetylome changes in epilepsy is still minimal, a further understanding of acetylation regulation will help us explore the pathological mechanism of epilepsy and provide novel ideas for treating epilepsy.

The differences in spatially optical properties between blue and green quantum wells (QWs) in a monolithic dual-wavelength semipolar (20-21) structure were investigated by scanning near-field optical microscopy (SNOM). The shortest wavelength for green QWs and the longest wavelength for blue QWs were both discovered in the region with the largest stress. It demonstrated that In composition, compared to stress, plays a negligible role in defining the peak wavelength for blue QWs, while for green QWs, In composition strongly affects the peak wavelength. For green QWs, significant photoluminescence enhancement was observed in the defect-free region, which was not found for blue QWs. Furthermore, the efficiency droop was aggravated in the defect-free region for green QWs but reduced for blue QWs. It indicates that carrier delocalization plays a more important role in the efficiency droop for QWs of good crystalline quality, which is experimentally pointed out for the first time.

Abstract A 3D ITO nanowire network with high quality by using polystyrene as an assisted material has been prepared, demonstrating superior optoelectronic performances with a sheet resistance of 193 Ω/sq at 96% transmission. Both remarkable flexibility tested under bending stress and excellent adhesion applied on special terrain substrate have been achieved. This method has led to a full coverage of micro-holes at a depth of 18 µm and a bottom spacing of only 1 µm, as well as a perfect gap-free coverage for micro-tubes and pyramid array. It has been proved that this 3D ITO nanowire network can be used as a transparent conductive layer for optoelectronic devices with any topography surface. Through the application on the micro-holes, -tubes and -pyramid array, some new characteristics of the 3D ITO nanowires in solar cells, sensors, micro-lasers and flexible LEDs have been found. Such 3D ITO nanowire networks could be fabricated directly on micro-irregular substrates, which will greatly promote the application of the heterotypic devices.

Abstract Background Double lumen intubation and one-lung ventilation should be applied without delay in cases of traumatic main bronchial rupture. In most cases, when the patients’ vital signs have been stabilized, the repair can be performed. However, when one-lung ventilation is complicated by traumatic wet lung, the mortality rate is likely to be much higher. Case presentation In this case, the patient experienced a left main bronchial rupture, bilateral traumatic wet lung, and acute respiratory distress syndrome (ARDS) because of severe thoracic trauma. Though the patient was treated with intubation and mechanical ventilation (MV), his oxygenation was still not stable. Thus, veno-venous extracorporeal membrane oxygenation (V-V ECMO) was initiated; upon improvement of oxygenation, the patient received an exploratory thoracotomy. Unfortunately, the rupture proved to be irreparable, resulting in a total left pneumonectomy. As there was severe ARDS caused by trauma, ECMO and ultra-low tidal volume (VT) MV strategy (3 ml/kg) were utilized for lung protection post-op. ECMO was sustained up to the 10th day, and MV until the 20th day, post-operation. With the support of MV, ECMO and other comprehensive measures, the patient made a recovery. Conclusion V-V ECMO and ultra-low VT MV helped this thoracic trauma patient survive the lung edema period and prevented ventilator associated pneumonia (VAP). In extreme situations, with the support of ECMO, the tidal volume may be lowered to 3 ml/kg.

Fe−doped hBN film has great potential for use in spintronic applications. The wafer scale preparation of Fe−doped hBN films and their material properties are crucial for application in devices. In this work, Fe−doped films with 2−inch wafer scale were fabricated by magnetron co−sputtering, and the properties of the films were characterized. The crystal quality decreased, but the electrical performance was greatly improved. The average square resistance of Fe−doped film was 0.34 KΩ/sqr. Meanwhile, the Fe−doped films kept the characteristics of hBN well. The wavelength of absorption edge was 216 nm, and the corresponding optical band gap of 5.76 eV.

A GaN ultraviolet photodetector with a petal-like β-Ga2O3 microcrystalline layer was prepared on the GaN template using electrochemical anodizing and annealing processes. The petal-like β-Ga2O3 microcrystalline layer was found to enhance the absorption of ultraviolet light and suppress the dark current, and a high responsivity from 230 nm (responsivity 8.5 A/W) to 400 nm (responsivity 0.1 A/W) was achieved by the photodetector. The rejection ratio of ultraviolet–visible light is greater than three orders of magnitude representing a high selectivity of ultraviolet light detection. The responsivity slopes of the photodetector under different biases were found to be strongly correlated with the wavelength of light, and the responsivity is much higher than that of conventional metal/insulator/metal wavelength identification photodetectors. This effective method of synthesizing β-Ga2O3 crystallites on GaN can be used to enhance the ultraviolet absorption of GaN photodetectors and improve the detection performance.

Block caving mining has the advantages of large production capacity, safe operation, low mining cost, and easy organization and management. Therefore, it is considered as one of the natural alternatives to the current open cut mining. The migration law of ore-rock and the design of ore drawing parameters during ore drawing are the key to block caving mining. The caving rocks usually contain pore water between the fine particles, therefore, the caving rock in an unsaturated state is a solid-liquid-gas three-phase coupling field. The electric double layer force as well as the ionic hydration force, electrostatic force, and Van der Waals force result in the interaction between adjacent particles on a molecular scale. However, the interaction is also resulted in the force of the liquid bridge. To explore the influence of moisture content on the shape of an isolated movement zone in block caving method under ore drawing in mesoscale, the stress between unsaturated ore particles was analyzed. The fine particles flow and discrete bulks of ore-rocks were investigated using lattice Boltzmann method (LBM) and discrete element method (DEM), respectively. Based on the LBM-DEM coupling algorithm, the ore-drawing models of the block caving method were constructed, and the relationship between the moisture content and the shape of the isolated movement zone was obtained. The accuracy and reliability of the ore-drawing models based on the LBM——DEM coupling algorithm were verified by comparing the simulation results with the existing research results. The results indicate that the moisture content of ore-rock has significant effects on the shape of the isolated movement zone. When the same ore-rock mass fraction is discharged, with an increase of moisture content, the height of isolated movement zone increases and then decreases, and the shape of isolated movement zone becomes slender and then is restored gradually. The critical value of moisture content during the change of isolated movement zone shape is about 10%.

We have fabricated a tubular whispering gallery mode laser based on InGaN/GaN quantum wells and transferred it onto a flexible substrate. Compared with those without the transferring processes, the threshold energy density was reduced by 60%, at about 25.55 µJ/cm2, while a high-quality factor of >15,000 was obtained. Finite-difference time-domain simulation demonstrated that such a low threshold energy density can be attributed to the decreased mode volume, from 1.32 × 10−3 μm3 to 6.92 × 10−4 μm3. The wavelength dependences on strain were found to be 5.83 nm, 1.38 nm, and 2.39 nm per stretching unit ε in the X, Y, and Z directions, respectively. Such strain sensitivity was attributed to the deformation of the GaN microtube and the change in the refractive index of the PDMS.

Abstract The fabrication and application of polystyrene (PS)-assisted ITO nanowire (NW) networks are reported. The ITO-NW networks are fabricated by means of electron-beam deposition via PS. This method has the advantages of low-temperature (~300 °C), low-cost, facile and efficient operation. The growth mechanism of PS-assisted ITO NWs was analyzed in detail, and the morphology of which could be regulated by the size of PS. X-ray diffraction and high-resolution transmission electron microscope show that the ITO NWs are close to an integral cubic lattice. The transmittance of ITO-NW networks layer is above 90% after 400 nm and the sheet resistance is ~200 Ω/□. When they applied on vertical blue and green LEDs, the light output power all has been improved ~30%. And, the resistive switching behaviors of ITO-NWs were measured and analyzed in Ag/ITO-NW networks/Al capacitor. The application of ITO-NW networks on special morphological devices was discussed. The PS-assisted ITO-NW networks show a strong researching and application value.

In this paper, the improvement of the method measuring the junction temperature of lightemitting diodes (LEDs) has been studied experimentally. A practical method is proposed with only three measurement procedures. With the consideration of indium (In) composition and blue shift, the method has a high applicability, which is practical for the LED chips vary from blue to green chips under different currents, including the packaged chips. On the other hand, according to the experimental and derived results, the junction-temperature difference and peak-wavelength shift in both blue-shift and red-shift fields show similar parabolic-like relations. To simplify the experimental processes, dual-wavelength LEDs were fabricated and measured instead of conventional single-wavelength LEDs.

To explore the percolation regulation and inducement of waste fine particles in ore drawing by the block caving method, a simulation is undertaken by using discrete element method software EDEM. This simulation contains coarse-to-fine particle amount ratio, diameter ratio and moisture content, and sets marker particles in different regions to trace the migration of adjacent coarse and fine particles. The results indicate that the ore-drawing advance dilution rate decreases with increasing coarse-to-fine particle amount ratio. The percolation rate of waste fine particles increases with increasing diameter ratio and is significantly affected by moisture content. Moreover, the percolation rate of fine particles is greater than the decline rate of adjacent coarse particles. The results provide a theoretical support for further studying and discussing the ore loss and dilution, determining the stope structure parameters and optimizing the ore drawing management system.

AB line and C line of Trans-Asia natural gas pipeline has attained a gas transmission capacity as 55 billion cubic meters per year. In recent years, pipeline transportation throughput accounts for about 20% of Chinese apparent consumption of natural gas. In order to ensure an economic and efficient operation of this transnational pipeline system, this paper conducts a comprehensive study on the joint operation of AB line and C line of Uzbekistan section of Trans-Asia natural gas pipeline. This paper innovatively puts forward “Methods of correction on multi-pressure head and multi-performance curve of centrifugal compressor”, aka. Data difference adjustment method”, to correct the factory performance curve of compressor, to ensure that the simulation accuracy is higher than 95%, and to provide support for operation decision-making. Based on the principle of minimum energy consumption of AB line and C line system of Trans-Asian natural gas pipeline, a set of optimal air intake allocation scheme between AB and C lines is studied and integration method of process operation scheme of AB line and C line are studied to support the optimum operation. Pipeline joint operation method for different hydraulic systems is studied. The pressure control principle by pressure balance method which realizes the joint operation of pipelines from different hydraulic systems is suggested for the first time, by which the pipeline operates stably. This paper studies the best location of 8 bridges reservations in AB line and C line in Uzbekistan, in order to enhance the comprehensively allocation capability of the whole system of transnational pipeline network in an all-round way, and to realize the function of energy conservation under normal conditions and of throughput guarantee under abnormal conditions. With additional bridges, pipeline transportation capacity can be increased up to 26 million m3/day and save energy consumption by up to 660 thousand m3/day under accident conditions. Keywords: Natural gas pipeline, Joint operation, Transmission allocation principle, Energy consumption

Heavily Sn-doped In2O3nano-pyramids with a Sn percentage of 19.97% by weight have been prepared by sputtering technique. The nano-pyramids with smooth facets and a sharp tip have been achieved by deposition on Sn-metal particles, leading to a diameter of ∼100nm. The gas sensors realized from these pyramids are highly sensitive to ethanol gas, and the sensitivity is about 133.99 against 200ppm ethanol at 250°C. Good sensitivity characteristics have been obtained even at a low temperature of down to 50°C. The high response and low working temperature demonstrate the potential application of heavily Sn-doped In2O3 nano-pyramids for fabricating gas sensors.

The thermo-viscoplastic behaviors of AISI 4140 steel are investigated over wide ranges of strain rate and deformation temperature by isothermal compression tests. Based on the experimental results, a unified viscoplastic constitutive model is proposed to describe the hot compressive deformation behaviors of the studied steel. In order to reasonably evaluate the work hardening behaviors, a strain hardening material constant (h0) is expressed as a function of deformation temperature and strain rate in the proposed constitutive model. Also, the sensitivity of initial value of internal variable s to the deformation temperature is discussed. Furthermore, it is found that the initial value of internal variable s can be expressed as a linear function of deformation temperature. Comparisons between the measured and predicted results confirm that the proposed constitutive model can give an accurate and precise estimate of the inelastic stress–strain relationships for the studied high-strength steel.

The hot deformation behaviors of a solution-treated Ni-based superalloy are investigated by hot compression tests over wide ranges of strain rate and forming temperature. Based on the experimental data, the effects of forming temperature and strain rate on the hot deformation behaviors are discussed in detail. Considering the effects of strain on material constants, comprehensive constitutive models are developed to describe the relationships between the flow stress, strain rate and forming temperature for the studied superalloy. The three-dimensional processing map is constructed to optimize the hot working parameters. Meanwhile, the microstructures are analyzed to correlate with the processing map. It is found that the flow stress is sensitive to the forming temperature, strain rate and deformation degree. With the increase of forming temperature or the decrease of strain rate, the flow stress significantly decreases. The predicted flow stresses agree well with experimentally measured results, which confirm that the developed constitutive model can accurately estimate the flow stress of the studied superalloy. The three-dimensional processing map shows that the optimum deformation windows for hot working are the domains with 980–1,040°C or 0.001–0.1 s−1$${{\rm{s}}^{- {\rm{1}}}}$$ when the strain is 0.6. Also, it is found that the dynamically recrystallized grain size increases with the increase of forming temperature or the decrease of strain rate.

The microcave array with extreme large aspect ratio was fabricated on the p-GaN capping layer followed by Ag nanoparticles preparation. The coupling distance between the dual-wavelength InGaN/GaN multiple quantum wells and the localized surface plasmon resonance was carefully characterized in nanometer scale by scanning near-field optical microscopy. The effects of coupling distance and excitation power on the enhancement of photoluminescence were investigated. The penetration depth was measured in the range of 39–55 nm depending on the excitation density. At low excitation power density, the maximum enhancement of 103 was achieved at the optimum coupling distance of 25 nm. Time-resolved photoluminescence shows that the recombination life time was shortened from 5.86 to 1.47 ns by the introduction of Ag nanoparticle plasmon resonance.

Ag coated microgroove with extreme large aspect-ratio of 500:1 was fabricated on p-GaN capping layer to investigate the coupling behavior between quantum wells and surface plasmon in highly spatial resolution. Significant photoluminescence enhancement was observed when the distance between Ag film and QWs was reduced from 220 nm to about 20 nm. A maximum enhancement ratio of 18-fold was achieved at the groove bottom where the surface plasmonic coupling was considered the strongest. Such enhancement ratio was found highly affected by the excitation power density. It also shows high correlation to the internal quantum efficiency as a function of coupling effect and a maximum Purcell Factor of 1.75 was estimated at maximum coupling effect, which matches number calculated independently from the time-resolved photoluminescence measurement. With such Purcell Factor, the efficiency was greatly enhanced and the droop was significantly suppressed.